Effect of postpyloric feeding on gastroesophageal regurgitation and pulmonary microaspiration: results of a randomized controlled trial.

OBJECTIVE To determine the extent to which postpyloric feeding reduces gastroesophageal regurgitation and pulmonary microaspiration in critically ill patients. DESIGN Randomized trial. SETTING A medical/surgical intensive care unit at a tertiary care hospital. PARTICIPANTS Intensive care unit patients were expected to remain ventilated >72 hrs. We excluded patients with esophageal, gastric, or small bowel surgery in the last week and patients with overt or clinically significant gastrointestinal bleeding. We studied 33 patients; 42.4% were female, mean age (sd) was 59.2 (+/- 16.8) yrs, and mean Acute Physiology and Chronic Health Evaluation II score was 22.5 (7.8). INTERVENTIONS Patients were randomized to gastric or postpyloric enteral feeds. Technetium 99-sulphur colloid was added to the feeds for 6 hrs of each of the first 3 days on study. MEASUREMENTS AND RESULTS We sampled the oropharynx and trachea hourly for the 6 hrs per day that patients received radioisotope-labeled enteral feeds, and the level of radioactivity in these specimens was measured. We defined an episode of gastroesophageal regurgitation and microaspiration as an increase in radioactivity >100 counts per minute/g. Patients fed into the stomach had more episodes of gastroesophageal regurgitation (39.8% vs. 24.9%, p =.04) and trended toward more microaspiration (7.5% vs. 3.9%, p =.22) compared with patients fed beyond the pylorus. When the logarithmic mean of the radioactivity count was compared across groups, there was a trend toward an increase in gastroesophageal regurgitation (3.7 vs. 2.9 counts/g, p =.22) and a trend toward increased microaspiration (1.9 vs. 1.4 counts/g, p =.09) in patients fed into the stomach. Patients who had gastroesophageal regurgitation were much more likely to aspirate than patients who did not have gastroesophageal regurgitation (odds ratio: 3.2; 95% confidence interval: 1.36, 7.77). CONCLUSIONS Feeding beyond the pylorus is associated with a significant reduction in gastroesophageal regurgitation and a trend toward less microaspiration.